The present invention relates generally to medical equipment and more particularly to an apparatus for applying traction to any of the major joints of the body. The apparatus of the present invention permits early motion and exercise of articular cartilage while manitaining distraction across the joint, thus reducing or eliminating post traumatic disorders such as arthritis, maintaining anotomic relations following surgical tissue repair of implantation, preventing tissue disruption, implant loosening or failure.
An external fixator can be used to hold two bones or bone fragments, such as for example, two pieces of a broken bone, in a fixed position relative to one another to facilitate the healing process. Generally speaking, pins are planted in the bone fragments and then the external fixator is secured to the pins to hold the pins, and the bone fragments attached thereto, in fixed position relative to each other.
In accordance with the present invention, an external fixation is provided which is well adapted to apply traction across a joint to allow reduction of intra-articular fractures by surrounding tissue pressure. Although this can be alternatively accomplished by use of traction conventionally provided by weights through the distal extremity at bed rest, this alternative has the disadvantage of not permitting the patient to move about so as to exercise the affected articular cartilage. Conventional external fixators are likewise not well adapted to permit exercise of the joint. Motion of a joint is useful in reducing or eliminating post traumatic disorders such as post traumatic arthritis which can be reduced or eliminated by proper exercise of cartilage. In short, by applying an external fixator of the present invention across a joint in a distraction mode, distension can be used to allow ligamentotaxis, i.e. tissue pressure reduction of the fracture.
The use of weights for applying traction through the distal extremities at bed rest has the disadvantage of not permitting the patient to move about so as to exercise the affected articular cartilage and conventional external fixators likewise not well adapted to permit exercise of the joint. Furthermore, when producing traction forces for tissue pressure reduction of the fracture, the magnitude of such forces should be adjustable and capable of ready measurement so that the proper traction can be applied to best suit the patient's needs.
Accordingly, the hinged external fixator of the present invention provides a portable traction device which can be applied to any of the major joints of the extremities, and selectively allow limited exercise of the joint which can be changed as therapy progresses. Post-traumatic or post-surgical stability of a joint is attained through such portable traction allowing early mobility and exercise even while aligning fracture fragments and injured tissues, or protecting surgical implants and/or tissue repairs. As will be further appreciated from the drawing and the disclosure which follows, the device of the present invention also provides readily adjustable traction or distraction forces and measurement thereof.